Claude Code wiki generation fails at ACP initialize with `Invalid params` (0.0.38)

[kwinstonix]

Environment

• Grok-Wiki desktop 0.0.38 (macOS Apple Silicon)
• Local agent: Claude Code (recent install via Homebrew)
• claude-agent-acp present on PATH
• Wiki format: Documentation, deep mode, local repository

Summary

Wiki/Docs generation fails immediately with Invalid params during the Claude ACP handshake. The same workflow succeeds when ACP is disabled.

Steps to reproduce

1. Install Grok-Wiki 0.0.38 and authenticate Claude Code locally.
2. Ensure claude-agent-acp is available (e.g. via npm i -g @agentclientprotocol/claude-agent-acp).
3. Start a local wiki/docs generation run with Claude Code as the agent.
4. Observe failure during structure phase.

Expected behavior

Generation proceeds past ACP initialization, similar to direct Claude Code spawning (Claude Code process spawned → Prompt sent to Claude Code).

Actual behavior

Run fails in ~1–2 seconds with:

• UI: Invalid params
• Agent notes stop at: Initializing Claude ACP session.

Event sequence (from local run history):

preparing → workspace-ready → starting
→ acp (Using ACP server …/claude-agent-acp)
→ spawned → acp-initialize
→ [retry with basic profile]
→ acp-initialize again
→ error: Invalid params

Compound knowledge profile retry does not help; failure occurs before any page generation.

Workaround

Disable ACP and use legacy direct Claude Code spawn:

GROK_WIKI_ACP=off open -a "Grok-Wiki"

After this, generation works as expected (direct Claude Code path).

Notes / suspected cause

On 0.0.38, Claude runs appear to prefer the ACP adapter when claude-agent-acp is detected. The failure happens at initialize, before session/new or prompt delivery.

This resembles other ACP clients hitting JSON-RPC -32602 Invalid params due to malformed initialize params (e.g. missing clientInfo.version, or clientCapabilities vs capabilities field mismatch). Worth checking runAcpStdioSession / ACP adapter initialization payload against the current ACP spec and claude-agent-acp expectations.

Suggested fixes

1. Fix ACP initialize payload for Claude adapter.
2. Or fall back to direct Claude Code spawn when ACP initialize fails (similar to pre-0.0.38 behavior).
3. Surface ACP stderr / JSON-RPC error details in the UI instead of generic Invalid params.